Method of assembling pipe couplings



1965 E. H. SCHUSTACK 3,163,779

METHOD OF A$SEMBLING PIPE COUPLINGS Filed April 6. 1964 2 Sheets-Sheet 1INVENTOR.

fan Aw H 50/0574CK BY MM ATMPNEY Feb. 9, 1965 E. H. SCHUSTACK 3,168,779

METHOD OF ASSEMBLING PIPE COUPLINGS Filed April 6, 1964 2 Sheets-Sheet 2INVEN TOR. farm/e0 H 5CHl/574CK METHOD-F ASSEMBLING PIPE COUPLINGSEdward H. Schustack, 1816 N. Stanley,

Los Angeles, Calif. Filed Apr. 6, 1964, Ser. No. 358,149

- 4 Claims. (Ci. 29-450) Thisinvention relates to a method of assemblingpipe couplings that may be used for metal pipe but is especially adaptedfor connecting pipe sections of asbestos-cement composition, or thelike, and known in the trade as cement p p p i 1 The conimon way of"connecting the adjacent ends of aligned cement pipes is to use.acoupling sleeve that loose ly 'fits over, said pipe ends and to sealbetween each pipe end. and the sleeve by means of a readily deformablegasket ofirubber, synthetic rubber or other suitable resilient material.It is common to house such gaskets in internalgrooves in the sleeve andto so compress them as to effect a hydraulic seal that withstandsconsiderable internal pressure'in the pipes. Since it is'important thatthe gaskets beunder substantial expanding pressure as induced by theirengagement withthe pipe ends, the same necessarily have a normal insidediameter smaller than the outside diameter of the portions of the pipearound 'which said gaskets fit. Hence, there is an interference fitbetween the pipe ends and the gaskets that frequently causes suchdistortion of the gaskets, when a coupling sleeve is applied, thatsealing efficiency is impaired. Cutting, tearing or other mutilation ofthe gaskets has occurred, the same having the further disadvantage ofnot showing up until leakage is revealed by hydraulic flow in the pipes.

This fault has been previously recognized and the usual way of lesseningthe possibility of gasket distortion and/ or mutilation is to taper orchamfer the ends of the pipes so that, by causing a gradual compressionof the gaskets as the pipe coupling is assembled, the same expandwithlittle or no distortion or mutilation and, therefore, seal effectively.Such chamfers are ordinarily machined on the pipe ends, enormously largelathes being used for this purpose. Thus, these chamfers are provided athigh cost. Also, while efiicient, as above explained, the tapers yetcreate considerable friction with the gaskets because there is arubber-to-cement rubbing contact that, if it can be lubricated at all,canbe lubricated only with such limited etiiciency as to reduce frictionto a small and inconsequential degree. i

Recognizing the foregoing and the shortcomings of common assemblypractice of gasket-provided couplings, this invention has foranobjectfto provide a novel, simple and improved method for effecting suchassembly with pipe ends that are square-ended (their normal condition),

thereby obtaining a leak-proof coupling assembly at low cost. p Theleast costly type of gasket that may be used is the one that has a roundcross-section. mize gasket mutilation, even though tapered pipe ends Inan effort to miniare-used, various other cross-sectional gasket formshave been used. Such variations in gasket cross-sectional form cost ofcement pipecouplings.

, A cordingly, another objectflofthe and feificient with 'roun' heihvention .alsb comp es nove ,7 ombihatloi is of e d rnethofd steps,which will appearfniore fu'lly in the eourse" -im'posea further costthat, when added to the cost of machiningtapers, on the pipe. ends,subtantially raises the o r 4 3 liid 'i ih O Patented Fra 9, 1965 1 ofthe following description of the present method or closes preferredembodiments ofihe present invention,

and the same are given by way of example only.

In the drawing, like reference characters designate similar parts in theseveral views. 7 1

FIG. 1 is a side elevational view, in quarter section, of a generallyconventional pipe coupling such as is assembled by the present method.

FIG. 2 is an enlarged and fragmentary longitudinal sectional viewshowing the beginning of the first step of one embodiment of the presentmethod.

FIG. 3 is a similar view showing the completion of the next method step.

FIG. 4 is a fragmentary cross-sectional view showing a preparatory stepin the internal expansion of one of i the sealing gaskets of, thecoupling as carried out in an a gasket by the means used in FIG; 4 andbefore inser- I tion of a pipe end into the coupling sleeve.

I FIG. 6 is a fragmentary longitudinal sectional view showing thebeginning of the first step of a modified method, said view beingcomparable to the first step as illustrated in FIG. 2.

FIG. 7 is a similar view showing a transition position of the means, asin FIG. 6, the same being intermediate the step of FIG. 6 and the nextstep, as exemplified in FIG. 3.

i As shown in FIG. 1, two pipes it and 11 are coupled by a sleeve 12,with compressed sealing gaskets i3 and 14 disposed in-the respectivegrooves 15 and 16 formed in the ends of sleeve 12 and in hydraulicsealing contact with the. outer faces of the respective pipes iii andif. The gaskets, as shown in FIG. 1, have a cross-sectional form that,in part, conform to the shape of grooves 15 and 16 and, in part, conformto the cylindrical outer surface of outer diameter that conforms to thediameter of the groove bottoms, andan inside diameter that is smallerthan the outer diameter of the pipes. In this case, whether the pipes 10and H are made of metal, cement or composition,- as before indicated,the respective ends 17 and it? are square-ended, i.e., without taperorchamfer.

The foregoing is generally typical coupling design, ex-

' cept that, as previously explained, the pipe ends 17 and 18 aresquare-ended rather than tapered.

The method that is illustratedin FEGS; 2 and 3 utilizes a plug it? thatis in the form of a metal ring with a re duced end 20 thatslidably fitsinto pipe it), as limited by an annular shoulder 21 that abuts pipe end17, and with a tapered end 22 at the end opposite to ,the reduced end2%. In practice, the outer size of said ring 19 is somewhat greater thanthatof pipe-iii, although said sizes may be alike, and the slope oftapered end 22 may beas gradual as practicable in preference to anabrupt orsharp taper. insertion of the plug endjZilinto pipe I it} maybe facilitated by slightlytapering the same, as

shownl p Withf'plug 19in place sane end of pipe iti and the taper ZZjlubrieat'ed, if desired, to, minimize friction, the

sleeve lzffw ith two'gaskets l3 and 14 in the: seats or grooveslfg-and'jliti thereof, is slippedoyer said taperjor the "taper, passagespip ewltl," is ,introdu sleeve- :As seenin FIG. 2, the-near gasket-i3will begradually compressed into the, groove by expansion of It willi beevident that thepresent meth "r ase gasket,

7 ing application," Serial-Noll 54,113,?11 ingtheiisametitle; e

itsinner diameter and, in the process, spread until, when 1 the outercylindrical surface of the plug reaches'the, gasket, the latter is'fully compressed and substantially fills the groove '15. The relativemovement of the sleeve and pipe 101s continued until the plug compressesthe gasket is as it did the gasket 13. By continuing such relativemovement of sleeve and pipe until the pipe end 17 pro- -jects beyond theend of the sleeve, the plug 19 may be removed, as shown in FIG. 3,leaving the pipe it} in position expanding both gaskets Hand 14. It willbe noted that only the taper on plug 19 causes such expansion,

7 the pipe iii only maintaining the same.

Now, by placing the end 18 of pipe 11 in end abut- ItrQllt with the pipeend 1'7, the pipes being aligned, of course, the sleeve 12. is eitherslid over the pipe 11 or the'two aligned pi es are moved longitudinallyso. that pipe 1% is retracted from its fully projected position, whilepipe 11' is projected into the sleeve. This achieves the positiongofFIG.;'1'wher'einthe expanded gasket 13 is engaged around pipe iii andthe expanded gasket 14 around pipe ll l. T he space shown betweenthepipe ends 17 and 13 is optional and is achieved by a small relativemovement of the pipes after, assembly as'shown. It will be evident thatthe present method entails the 1 expansion of both gaskets ofthecoupling and'mziintaining of the expansion by one of the pipes beforethe other steps or methods that may fall within the scope of the 1 Whilethe foregoing discloses what plated to be the best mode of carrying'outthe invention,

the same is, of course, subject to'modificatio n without departing fromthejspirit and, scope of the invention. Therefore, it is nottdesired torestrict the invention to the particular method steps or combinati-oniorsequence of method steps described, but to cover allequivalent appendedclaims.

Having thus described the invention, what claimed 7 and desired to besecured by Letters Patent is:

,-1. The method of assembling a coupling sleeve ov r the adjacent endsof two pipes, the sleeve being provided withtwo annular gaskets that aredisposed in inwardly open and longitudinally spaced annulargrooves andare adapted to seal around the respective pipes, said method consistingin first expanding the inner diameter of one gasket while simultaneouslyradially compressing'the same into itsgroove and thenfexpanding theiinnerj di- V I ameter of the other gasket whilesimultaneously'radially.

compressing the same into its groove while retaining the pipe'is'movedinto engagement with the 'gasket that seals it; also, that both pipeends may he square-ended and that the plug is re-usable as needed, oneplug serving to aid in the connection of the-successive coupling of apipe line. e e

In the modification of FIGS. 4 and 5, a gasket-expanding ring 25, incollapsed condition as in, FIGi 4, is placed within the gasket 13 or 14,as the case maybe. Then, by operating a tool 26' to expand said ring,the latter is nlargedito the condition of 1 1G 51 Thus, a pipe may beslid into the expanded gasket while displacing the ring 25, whichcollapses in the process and is ready for re-use.

By providing one end of ring 5 witha round eye 27 and the other endwithan elongated eye 28, two laterally directed pins 29 and (it? on saidtool, engagedin said eyes,

Vi may be relatively moved by manipulation of the tool-to cause theangled ends 31 of the ring to sl-idingly engage to spread the ring. Onesuch ring and tool may serve to spread both gaskets in the sleeve, onea-fter'the other.

It will be evident that the present method may be carried out with themeans shown in FIGS. 4 and 5. Also,

any sectional or segmentalmeans capable of being spread to causeexpansion of thegasketsld and '14 will serve in the present connection.

It will be noted that-the method which is described in'connection withFIGSL -2 and 3 provides forinsertion of the end 17 'of 'pipe it? intothe gasket 13 before the gasket :14- has been expanded. This is due tothe use of a relatively short gasket-expanding plug 1%." The methodillustratedin'the embodiment of FIGS.

6 and 7 provides for insertion of the pipe end 17 into the gasketlSjatter thegasket 14- has been expanded. Thus, both gaskets l3 and-1dare held expanded by the K "plug 1% before the pipe end 17 achievesexpanding engagement with the gasket 13. fThis transition position is fshown in PEG. 7. Itwilloe-clear that, as the pipe it) t ismoved further'into the "sleeve 12 or the sleeve is slid further onto pipe it), saidpipewill'be positioned, as in FlG.,3,with the plug llfiwhollyremovcdfrom engage- I ,Inent withthe gafsketld the latter gasket to bring theabutted ends of the twoinitial longitudinal spacing of the two'gaskets,inserting 1 i the end of:one pipe intothe first-expanded gasket and theninto the other gasket so that said one pipe maintains bothlongitudinally spaced gaskets expanded, plac:

ing the end of the other pipe in abutment against the i mentioned end ofthe (first pipe, and, finally, movingthe' sleeve together with thelongitudinally spaced gaskets with their increasedinner diameter andradial compression into'said grooves relatively toithei abutted pipesto;

slidingly retract the. first pipe from engagement by said other gasketand slidingly project said other pipe through pipes to a positionintermediate thev gaskets.

' 2. The method of assembling a coupling sleeve over the adjacent endsof two pipes, the sleeve being provided with two annular gaskets t-hatare disposed ininwardly open and longitudinally spaced annular groovesand are adapted to seal around the respective'pipes, and in which bothpipe. ends have end faces that are normal to the Y pipe axes and theouter cylindrical faces of said pipes terminate at said ends, saidmethod consisting in first expanding the inner diameter -of one gasketto a size approximating theouter diametral size of the pipes whilesimultaneously radially compressing the same into its groove and thensimilarly expanding the inner-diameter of the other gasket whilesimultaneously radially com pressing the same into its groove whileretaining the initial longitudinal spacing of the two gaskets, insertingthe end of one pipe intothe first-expanded gasket and then 'into theother gasket so that said one pipe maintains both longitudinally spacedgaskets expanded, placing the end of the other pipein abutment againstthe mentioned end of the first pipe, and, finally, moving the sleeveto-. v

gether with the longitudinally. spaced gaskets'withtheir increased innerdiameter. and radial compression into said grooves relatively to theabutted pipes to slidingly retract the first pipe from engagementbysaidt otherigasket and slidingly project said other pipethroughitheilatter gasket to bring the abutted end s of the twofpipes to"a position intermediatethe gaskets. f e

' 3. The method of assembling a coupling sleevefover the'adjacent endsof two, pipes, the sleeve being provided -The l niethod is completediadescribed above respectcg ing the alignment of pipes ltl anld ll andrelativern-ove ment of the sleeve and'said aligned pipes;

a' 'continu atiori-i pa his application is V ow ah andone'd, bear- I Qgasket while simultaneously radi jsarne into itsg'r ove-arid' thenexpand g i with two annular gaskets that are disposed i n inwardly openand longitudinally spaced annular grooves and are" adapted to sealaround the respective pipeshsaid method consisti ""in;first-.expanding"theinnerdiarrieter of one v 11y mpre the 'adially,

is now oontern 1y spaced gaskets expanded, placing the end of the otherpipe in abutment against the mentioned end of the first pipe, and,finally, moving the sleeve together with the longitudinally spacedgaskets with their increased inner diameter and radial compression intosaid grooves relatively to the abutted pipes to slidingly retract thefirst pipe from engagement by said other gasket and slidingly projectsaid other pipe through the latter gasket to bring the abutted ends ofthe two pipe to a position intermediate the gaskets.

4. The method of assembling a coupling sleeve over the adjacent ends oftwo pipes, the sleeve being provided with two annular gaskets that aredisposed in inwardly open and longitudinally spaced annular grooves andare adapted to seal around the. respective pipes, and in which both pipeends have end faces that are normal to the pipe axes and the outercylindrical 'faces of said pipes terminate at said ends, said methodconsisting in first expanding the inner diameter of one gasket to a sizeappnoximating the outer diametral size of the pipes while simultaneuoslyradially compressing the same into its groove and then similarlyexpanding the inner diameter of the other gasket While simultaneouslyradially compressing the same into its groove while retaining theinitial longitudinal spacing of the two gaskets, inserting the end ofone pipe into the first-expanded gasket before the second gasket hasbeen expanded, and then into the other gasket so that said one pipemaintains both longitudinally spaced gaskets expanded, placing the endof the other pipe in abutment against the mentioned end of the firstpipe, and, finally, moving the sleeve together with the longitudinallyspaced gaskets with their increased inner diameter and radialcompression into said grooves relatively to the abutted pipes toslidingly retract the first pipe from engagement by said other gasketand slidingly project said other pipe through the latter gasket to bringthe abutted ends of the two pipes to a position intermediate thegaskets.

References Cited in the file of this patent UNITED STATES PATENTS

1. THE METHOD OF ASSEMBLING A COUPLING SLEEVE OVER THE ADJACENT ENDS OFTWO PIPES, THE SLEEVE BEING PROVIDED WITH TWO ANNULAR GASKETS THAT AREDISPOSED IN INWARDLY OPEN AND LONGITUDINALLY SPACED ANNULAR GROOVES ANDARE ADAPTED TO SEAL AROUND THE RESPECTIVE PIPES, SAID METHOD CONSISTINGIN FIRST EXPANDING THE INNER DIAMETER OF ONE GASKET WHILE SIMULTANEOUSLYRADIALLY COMPRESSING THE SAME INTO ITS GROOVE AND THEN EXPANDING THEINNER DIAMETER OF THE OTHER GADKET WHILE SIMULTANEOUSLY RADIALLYCOMPRESSING THE SAME INTO ITS GROOVE WHILE RETAINING THE INITIALLONGITUDINAL SPACING OF THE TWO GASKETS, INSERTING THE END OF ONE PIPEINTO THE FIRST-EXPANDED GASKET AND THEN INTO THE OTHER GASKET SO THATSAID ONE PIPE MAINTAINS BOTH LONGITUDINALLY SPACED GASKETS EXPANDED,PLACING THE END OF THE OTHER PIPE IN ABUTMENT AGAINST THE MENTIONED ENDOF THE FIRST PIPE IN ABUTMENT AGAINST THE SLEEVE TOGETHER WITH THELONGITUDINALLY SPACED GASKETS WITH THEIR INCREASED INNER DIAMETER ANDRADIAL COMPRESSION INTO SAID GROOVES RELATIVELY TO THE ABUTTED PIPES TOSLIDINGLY RETRACT THE FIRST PIPE FROM ENGAGEMENT BY SAID OTHER GASKETAND SLIDINGLY PROJECT SAID OTHER PIPE THROUGH THE LATTER GASKET TO BRINGTHE ABUTTED ENDS OF THE TWO PIPES TO A POSITION INTERMEDIATE THEGASKETS.